CHAIN VALLEY MINE

From Bord & Pillar to Longwall

Longwall Conference – 2012 –

MineLocation

• Chain Valley is located in the Newcastle coalfield on the southern shores of Lake Macquarie, around 100 klm north of Sydney.

• The mine is immediately adjacent to Delta Electricity's Vales Point power station, one of Chain Valley's major customers.

• Mine leases cover an area of 2100 hectares, with access to three mineable seams

• Current JORC estimates are 25 Mt of recoverable thermal product.

• The mine has had many owners since its commencement in August 1962.

• LDO Coal acquired part ownership of Chain Valley in 2009 with full acquisition effected in December 2010.

• Current markets consist of both export and domestic with target production of 1.2Mt per annum.

Chain Valley

History of Chain Valley

Review of Strata ManagementSystem

• A full analysis of geotechnical issues at the mine was undertaken in 2010 incorporating:

– Establishment of the Authority to Mine process

– Regular Strata Control Committee meetings

– Extensive strata monitoring and review

– Extensive geological mapping

– Specialist geotechnical training sessions

– Open forum with employees

– Audit and Review process to refine strata support plan

From Bord & Pillar toLongwall

• Following review of the Strata Management System it became evident the mine could not be successful with place change mining.

• In late 2010 a decision was made to change the method of mining at Chain Valley from a bord-and-pillar operation to the Longwall mining method along with utilising bolter miners.

From Bord & Pillar toLongwall

• The first bolter miner arrived in December 2010 to drive the Tailgate of Longwall 1 and the second JOY 12CM30 arrived in the first quarter of 2011.

• Capital required

• Lead time of Longwall components

• Departmental approval

• Mine culture toward new mining method of mining

• Whole of workforce training in new mining method

Challenges for LW

Challenges

• Ventilation upgrade to facilitate new mining method

• The mine’s conveyor system, incorporating:

– Underground bin capacity

– Cable belt throughput

– Surface bin throughput

– Crushing plant throughput

Challenges

Longwall Supplier Selection

• Developed a close relationship with a Chinese manufacturer for the supply of mechanical and structural components of a longwall mining system.

• The main drivers for this liaison were:

1. Price

2. Availability

3. Design-build to mine requirements

Longwall Build• Business risk assessment was

undertaken from the viewpoint of utilising unproven Chinese equipment in Australia.

• Use of Chinese motors that required IEC approval.

• During construction process audits and design verification were undertaken by a third party.

• Supports tested to Consol 30K cycles with an exceptional outcome –previously never undertaken in China

Longwall Specifications

Width … 61m – 85m

Length … 910m to 1700m

Shearer manufacturer … Bucyrus

Type … Electra EL 2000 DERDS

Drum diameter … MG - 2m – TG – 2m

Cutting height / method /web depth … 3.2 – 3.5 m / Uni-di / 750mm

Install power … 1275 kW

Roof support manufacturer … SIWEI

Longwall SpecificationsType Number of supports … 2-leg chock shield / 38-52

Yield load/ working range/control … 800 t / 1.8 – 3.9 m / Tiefenbach

Tip to Face 400mm

Face conveyor manufacturer … IMM , SGZ800/200 twin inboard

1000tph capacity

Chain speed & manufacturer … 1.2 m/s / Parsons

AFC Motors … 1 x 250 kW

Beam stageloader … IMM, SZZ800/200, 200 kW

Coal crusher … IMM, PLM 2000, 200 kW

Coal clearance (to surface)type/capacity … Conveyor / 500tph

Longwall Implementation

• 61.5m Longwall commenced MW Block 1 in September 2011 –10 months from conception to implementation.

• Extensive training undertaken for very inexperienced workforce.

• Currently mining block 3 with higher than expected reliability and performance being achieved.

• In June 2012 block 3 was extended to 85m adding an additional 14 roof supports and AFC components.

Chain Valley is the first underground mine to implement andsuccessfully complete a Chinese manufactured longwall in Australia

Chain Valley Extension